Centrifugal pump



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H. F. SCHMIDT CENTRIFUGAL PUMP Filed March 6, 1925 INVENTOR ATTORN EY Patented Feb. i 14, 192.8.

lUNITED STATES PATENT OFFICE.

HENRY F. SCHMIDT, OF ITANSDOWNE, PENNSYLVANIA, ASSIGNOR TO WES'IIN'GHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA,

CENTRIFUGAL PUMP.

Application filed March 6, 1925. Serial No. 13,596.

My invention relates to impeller pumps of the type in which a Huid is delivered from an impeller to a collecting chamber, such as a volute, which increases in sectional iiow 5 area at a greater rate than is necessary to provide for a constant velocity throughout lthe collecting chamFber.

In pumps of this type there have been losses, in efficiency vdue to the formation of i eddies at the points of meeting of the uid discharged from the several vanes of the impeller. In order to avoid this loss it has heretofore been proposed to 'insert guide vanes in the space immediately surrounding the impeller. While'this has increased the efficiency yet it has occasioned other losses due to the fact that bodies of iiuid moving at different velocities must combine and take on a common velocity. This combination results in a shock which absorbs energy and lowers the eiciency. In order to avoid this last mentioned loss I propose to construct an impeller pump in which the guide vanes and the collecting passage are so shaped and arranged that the velocity of the Huid in the collecting.chamberopposite the opening between any two guide vanes will be the same as Ythat of the iiuid discharged from-between the guide vanes. u

Thus one of the principal objects of my invention is to provide a pump which will have the collecting passage and the guide vanes so proportioned and arranged that the A various streams of fluid will co-mingle with- Tout the shock due to the fact that they are moving at substantially the same velocities just before they co-mingle. Another object of my1 invention is to provide an improved pump which will be simple, compact, durable, efficient in operation and inexpensive to manufacture.

IVith these and other objects in view, which will become apparent as the description pro ceeds, the invention resides in the construction, combination andarrangement of parts hereinafter more fullydescribed and claimed and illustrated in the accompanying drawings wherein: Fig. 1 represents a vertical section of a pump embodying ene form of 5o my invention, the section being taken on the line I-I of Fig. 2 and: Fig. 2 represents a vertical section taken on the line II-II of Fig.l 1. i

In' the drawings .10 represents a pump constructed in accordance with my invention in `apparatus in which which the fluid to be pumped is delivered, to a chamber '11 from whence it flows to an. impeller 12. The impeller is mounted on a shaft 13 which is jonrnaled at 14 in a casing l'surroundlng the chamber 11. The rotation of the impeller 12 carries the fluid with it and it is discharged from the impeller with substantially the tip velocity into a.

volute passage 18. This passage 18 is provided with a plurality of guide vanes 19 which diverge outwardly towards a collecting chamber 21. This chamber is also of a volute shape and communicates with a discharge opening 23. Due to the increase in area of the collecting chamber the fluid moving therein will move more slowly as it approaches the discharge opening 23. Y order that the fluid discharged from between the guide vanes19 may co-mingle with the fluid in the collecting chamber without shock I make the divergence between the vanes near the end -of the collecting chamber greaterthan that near the beginning thereof. This also results in these guide vanes being longer than those nearer the beginnin of the collecting chamber. As a result o these two conditions, it is possible to have the iuid from between the guide vanes mov- 'ing at the same velocity as the iuid in the collecting chamber opposite ltheir opening at the time these uids Vco-mingle.

It will be seen that I have devised an the losses due to shock at points of co-mingling are entirely eliminated. This results in a device which is not only more efficient but which is free from vibrations which are present in other pumps, due to the above mentioned shock.

While I have shown my invention in but one form, it will be obvious to those skilled in the 4art that 1t 1s not so limited, but is susceptible of various other changes and modifications, without departing from the spirit thereof, and I desire, therefore, that only such limitations shallbe placed thereupon as are imposed by the prior art or as are specifically set forth in the appended claimsv Y What I claim is J1.. A fluid translating device comprising an impeller for delivering fluid at substantially uniform velocity, a collection chamber for receiving iuid from the impeller and for conducting fluid at various velocities, and means for delivering iuid from the impeller 110 to the collection chamber at substantially the velocity of the fluid in the collection chamber at the oint of delivery thereto.

2. A uld translating device comprising an impeller, a collection chamber for decreasing the velocity of fluid in the direction of flow therethrough, and means for delivering fluid from the impeller to the collection chamber at substantially the velocity of the fluid in the collection chamber at the point of delivery thereto.

3. A fluid translating device comprising an impeller', a collection chamber for decreasing the velocity of fluid in the direction of flou7 therethrough, and means between the impeller and the collection chamber providing a plurality of passages having their respective ratios of inlet to outlet area progressively decreasing in the direction of flow through the collection chamber.

4. A fluid translating device comprising an impeller, a collection chamber for decreasing the velocity of fluid in the direction of flow therethrough, and a plurality of guide vanes interposed between the impeller and the collection chamber and arranged to provide a plurality of passages having their respective ratios of inlet to outlet area progressively decreasing in the direction of flow through the collection chamber'.

5. A pump comprising an impeller chamber, an impeller in the chamber, a divergent collecting chamber, a volute passage way zone between said chambers, and guide vanes of progressively increasing length in said passage way Zone for dividing said Zone into a plurality of passages Whose exit areas are progressively larger with progressively larger collecting chamber cross sectional areas.

6. A pump comprising an impeller chamber, an impeller in the chamber, a collecting Lescure chamber, a. volute passage way zone between said chambers, and stationary guide vanes of progressively increasing length in said passa-ge Way zone.

` 7. A pump comprising an impeller from which liquid is delivered at equal velocity from substantially its entire periphery, a collecting chamber through which liquid is moving at varying velocities and a series of passages for delivering liquid from said impeller to said collecting chamber at the same velocity as the liquid in the collecting cl1a1nber at the point Where the liquid is delivered.

8. A pump comprising a. chamber from which fluid is delivered at a constant velocity, a chamber through which fluid is moved at a decreasing velocity and means for delivering fluid from said first chamber to said 'second chamber at the same velocity as the fluid in the second chamber at the point Where it is delivered.

9. A fluid translating device comprising an impeller, a collecting chamber having an inlet and a discharge end for receiving the liquid discharged from the impeller and for reducing its velocity of flow, and a series of diverging passages connecting the impeller and the collecting chamber, the lengths of the respective passages increasing toward the discharge end of the collecting chamber.

10. In a pump, the combination of an ixnpeller chamber, an impeller in the chamber, a volute collecting chamber, a volute passage Way zone between the impeller chamber and the collecting chamber and diverging in the same sense with the latter, and guide vanes of progressively increasing length in said passage Way zone.

In testimony whereof, I have hereunto subscribed my name this second day ot March 1925.

HENRY F. SCHMIDT. 

